Wondering what's new in the 2.1 "krogoth" release? Check this What's New in 2.1 wiki page to find out!
Linaro is a collaborative organization whose goal is to promote ARM processors within the Linux community, which they have done very successfully since 2010. The Yocto Project is very pleased to announce Linaro as a Silver Member. Welcome!
The Yocto Project is composed of many different internal projects. Most of these are maintained by the Yocto Project's maintainers. Some of these, like BitBake and OpenEmbedded Core, are co-maintained with other projects.
One internal project, Poky, is a reference system that composes all of these internal projects together and provides a single base to test interoperability. When you download a comprehensive version of the Yocto Project, you are actually downloading Poky - inside, all of the components work together. Think of it as a base from which to start customizing your own Linux distribution.